<!DOCTYPE html>
<style>
div.nine::before { content: '9: '; }
div.ten::before { content: '10: '; }
div.eleven::before { content: '11: '; }
</style>
<div>
    <div class='nine'>Nine</div>
    <div class='ten'>Ten</div>
    <div class='eleven'>Eleven</div>
</div>
</html>
